Concrete form



i Jan. 19, 1943.

CONCRETE Filed Feb. 23. 1942 H. G. DAvls FORM 2 Sheets-Sheet l INVENTOR.

` Arran/yn i 381mm 19435' H. cs. DAvls 2,308,806

CONCRETE FORM 'Filed Feb. 2s, 1942 2 'sheets-sheet 2 Patented Jan. 19, 1943 UNITED STATES PATENT OFFICE CONCRETE FORM Harold Greenleaf Davis, Denver, Colo. Application February 23, 1942, Serial No. 431,979

(c1. f2s-131.5)

6 Claims.

This invention relates to a supporting form for concrete structures and more particularly to a form of the one-side type against which the concrete aggregate is thrown in any suitable manner such as by means of a compressed air operated cement gun.

The principal object of the invention is to provide a series of connectable members which can be quickly and easily assembled to follow the planned lines of any desired structure and which can be disassembled without damage for reuse as often as desired.

Another object of the invention is to provide a sectional metallic form support to which a Wooden form wall may be attached by means of ordinary carpenters nails and which can be quickly and easily removed from the nails without damage to the supports or to the wood wall members.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efficiency. These will become more apparent from the following description.

In the following detailed description of the invention reference is had to the accompanying drawings which form a part hereof. Like numerals refer to like parts in all Views of the drawings and throughout the description.

In the drawings:

Fig. 1 is a cross section through a typical concrete structure of the igloo or bomb shelter type showing the invention in place therein;

Fig. 2 is an enlarged fragmentary detail section through a corner of the improved form, taken on the line 2-2, Fig. 1;

Fig. 3 is a detail section through one of the rib members, taken on the line 3 3, Fig. l;

Fig. 4 is a further enlarged section through a rib member;

Fig. 5 is a detail, perspective View of one of the straight rib bars employed in the invention;

Fig. 6 is a similar view of one of the curved rib bars;

Fig. 7 is a similar view of a corner member;

Fig. 8 is a similar View of an angle clip employed for connecting the various members;

Fig. 9 is a perspective View of an alternate form of rib bar; and

Fig. 10 is a fragmentary section illustrating the alternate form in use.

The improved core form employs a plurality of similar, straight rib bars I0 (as illustrated in Fig. 5), each bar being punched with a plurality of spaced-apart bolt holes II adjacent one of its edges, and a series of curved or arch bars I1 which are curved upon various radii to be selected for the required job. Both types of bars carry facing strips of corrugated metal I2 on one of their faces. The corrugations in the strips extend longitudinally of the bars and are secured to the bars in any desired manner such as spot welding or soldering them along one edge thereof as indicated at I3.

In use two of the bars I0 and/ or two of the bars I'I are bolted together, by means of suitable clamp bolts I4, with their corrugated strips in Contact to form the rib members for the form. Any desired number of the bars may be secured end to end to form rib members of any desired length or curvature. The ends of the bars are detachably secured together by means of angle clips I5 and attachment bolts 23. The angle clips are secured by the bolts I4 passing through the end bolt holes I I of the bars. The clips contain two bolt holes I6 for this purpose so that they may be used on either side of the bars.

Square corner members I8 are provided for forming the joints between the sides and ends of the form and also between the top and ends thereof. The corner members have tapped screw holes I9 corresponding in spacing to the bolt holes II in the bars so that the latter may be secured against the corner members by means of suitable cap screws 20. Two adjacent sides of the corner members carry the corrugated strips I2 attached thereto.

Let us assume that it is desired to erect a form for a building which is rectangular in plan with a longitudinally extending arched roof as shown in Fig. 1. The oor, indicated at 2l, is rst poured. An angle iron oor frame 22 is attached to the floor outlining the inner wall line thereon. Vertical rib members are attached to the floor frame at spaced-apart intervals along each side thereof by means of the clips I5. Each' of the vertical rib members consists of two of the bars I0 with their corrugated strips therebetween and the bars are connected together by means of the angle clips I5 and attachment bolts 23, until the arch line is reached.

At this point, rod attachment plates 24 are secured between the coacting bars of each' rib. These plates are provided with openings for receiving the hooked extremities of an extensible tie rod 25 provided with a suitable turnbuckle 26. 'I'he tie rods are adjusted to hold the ribs vertical and act to prevent the ribs at the opposite sides from swinging or tilting outwardly.

The .arch bars I'I are now secured together and to the top of the vertical rib members and Figs. 9 and 10, could be used.

Varea between the bars. edges of the bars may be drawn completely vtocontinued across the top of the form. The corner members I8 are set up at each corner and arched across the top similarly to the arch bars. One of the bars I is secured to one side of each corner member and another bar III is secured to the adjacentI side as illustrated in Fig. 2. 'I'he vertical ribs are continued across the ends of the floor up to the arched corner members, as shown in Fig. 1.

It will be noted that the bolts I4 and the screws '20 are positioned near the outer edges of the bars. Suitable screw clamps 21 may be placed along the inner edges of the bars to clamp them toward each other if necessary. These clamps become more necessary if relatively wide Y bars are used as illustrated in Fig. 10. Theentire form support has now been erected.

Sheets Vof wood plyboard 28, or other iexibleV ,to prevent withdrawal thereof.

The board 28 is bent over the roof arch and nailedthereto similarly to the side wall boards. Window and door forms 30 may be attached on the outside of the plyboard if desired.

The entire form is now sprayed with concrete aggregate to the desired thickness by means of power operated cement guns to form the com- Y plete concrete 'wall as illustrated at 3l.

` After the concrete has set, the tie rods 25 are I 0 of each rib'together, are loosened so that the grip onthe nails will bereleased and the ribs may be disassembled and removed. The plyboards usually drop from the wall after the ribs are removed. However, should they adhere thereto, the projecting nails may be gripped with pliers to pull the boards from place. The nails are driven from the boards and all of the ele-V ments are ready for reuse. V

' Should the forms be required for exceedingly heavy work, extra widebars 32, as illustrated in In this event, however, the corrugated strip need not be the full width' of the bar, as indicated in Fig. 9, since its function is only to provide a nail gripping In this case the inner gether, as indicated in Fig. 10, to provide better grip for the extremities of the nails. The angle clips are secured together, and to the floor frame bythe single bolts passing through single holes 33 in the clips so that the clips may rotate as the clamps 21 are tightened. The corner Vmerribers I8 are also furnished both straight and on removed and the bolts I4, securing the two bars been described Vand illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims,

without departing from the spirit of the inven-V Y tion.

Having thus described the invention, what is claimed and desired secured by Letters Patent p 1. An inner form for receiving a concrete facing comprising: a plurality of rib bars detachably secured together in pairs in face-tcface relation to form rib members; sheet material positioned against the edges of the rib members; nail engaging strips on the adjacent faces of thebars of each pair; and nails extending through the sheet material and between the nail engaging strips of the rib members, said nails being releasable by separation of the strips.

2. A rib member for supporting the wall of a concrete form comprising: tWo similar bars; a strip of corrugated material against one face of each bar; means for clamping the two bars together with their corrugated strips, therebetween so that the latter will frictionally engage nails driven through said wall between said bars.

3. vA rib member for supporting the wall of a concrete form comprising: two similar bars;

means for detachably securing the two bars to- Y gether in face-to-face relation; Vand corrugated metal clamped between the two bars for receiving and frictionallyv engaging nails driven concrete forniV comprising: twoV similar bars; VaV

strip of corrugated metal secured against one face of each' bar, the corrugations ofthefstrip extending longitudinally of the'bar; boltsv secur- 1 ing the bars together with the corrugated strips in contact, the adjacent Vcorrugated-'strips forming clamping means for Lfrictionally engaging nails driven through said wall between' said bars.

6. A supporting member Vfor concrete forms comprising: two longitudinally extending bars; means for clamping the two bars' togetherfcorrugated strips of metal secured tothe adjacent faces oi said bars for receiving a nailV therebetween.

HAROLD GREENLEAF DAvrs. 

